Finger devices with proximity sensors

ABSTRACT

A system may include one or more finger devices that gather input from a user&#39;s fingers. The system may include control circuitry that sends control signals to an electronic device based on the input gathered with the finger devices. A finger device may include one or more proximity sensors that measure a distance to the user&#39;s finger. The proximity sensor may be a self-mixing optical proximity sensor having a laser and photodiode. The proximity sensor may have submicron resolution and may be configured to detect very small movements of the finger as finger pad is moved around by a thumb finger, by a surface, and/or by other finger movements. The proximity sensor may measure changes in distance between the proximity sensor and a flexible membrane that rests against a side portion of the user&#39;s finger.

This application claims the benefit of provisional patent applicationNo. 62/904,540, filed Sep. 23, 2019, which is hereby incorporated byreference herein in its entirety.

FIELD

This relates generally to electronic devices, and, more particularly, tosensors for finger-mounted electronic devices.

BACKGROUND

Electronic devices such as computers can be controlled using computermice and other input accessories. In virtual reality systems,force-feedback gloves can be used to control virtual objects. Cellulartelephones may have touch screen displays and vibrators that are used tocreate haptic feedback in response to touch input.

Devices such as these may not be convenient for a user, may becumbersome or uncomfortable, or may provide inadequate feedback.

SUMMARY

A system may include one or more finger devices that gather input from auser's fingers. The system may include control circuitry that sendscontrol signals to an electronic device based on the input gathered withthe finger devices.

A finger device may include one or more proximity sensors that measure adistance to the user's finger. The proximity sensor may be an opticalproximity sensor such as a self-mixing interferometric optical proximitysensor having a laser and photodiode. The proximity sensor may havesubmicron resolution and may be configured to detect very smallmovements of the user's finger skin as the finger pad is moved around bya thumb finger, by a surface, and/or by other finger movements. Theproximity sensor may measure changes in distance between the proximitysensor and a flexible membrane that rests against a side portion of theuser's finger.

A self-mixing proximity sensor may have a coherent or partially coherentsource of electromagnetic radiation. The source of radiation may, forexample, be a coherent light source such as an infrared vertical cavitysurface-emitting laser, a quantum cascade laser, or other laser. Theself-mixing proximity sensor may also have a light detector such as aphotodiode and/or other electromagnetic-radiation-sensitive element. Thephotodiode may be stacked with the laser and/or may be an intra-cavityphotodiode that is located within the laser cavity.

The control circuitry can modulate the laser bias current signal toproduce a target distance measurement corresponding to an absolutedistance between the self-mixing proximity sensor and the user's finger(or a flexible membrane that rests against the user's finger). Thismodulation can enable the detection of the relative displacement of theuser's finger (or a flexible membrane resting against the user'sfinger).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of an illustrative system with a fingerdevice in accordance with an embodiment.

FIG. 2 is a top view of an illustrative finger of a user on which afinger device has been placed in accordance with an embodiment.

FIG. 3 is a cross-sectional side view of an illustrative finger deviceon the finger of a user in accordance with an embodiment.

FIG. 4 is a top view of an illustrative finger device with displacementsensors in accordance with an embodiment.

FIG. 5 is a perspective view of an illustrative finger device measuringmovement of a finger as the user contacts the finger with another fingerin accordance with an embodiment.

FIG. 6 is a perspective view of an illustrative finger device measuringmovement of a finger as the finger contacts a surface in accordance withan embodiment.

FIGS. 7, 8, and 9 are top views of a finger making illustrative fingermovements that may be detected with a finger device in accordance withembodiments.

FIG. 10 is a top view of an illustrative finger device being used todetect an adjacent finger in accordance with an embodiment.

FIG. 11 is a perspective view of an illustrative finger device beingused to detect input on the side of the finger device in accordance withan embodiment.

FIG. 12 is a perspective view of an illustrative finger device beingused to detect input on an upper portion of the finger device inaccordance with an embodiment.

FIG. 13 is a perspective view of an illustrative finger device beingused to detect input as the user holds an object in accordance with anembodiment.

FIG. 14 is a perspective view of an illustrative finger device beingused to detect a finger curling movement in accordance with anembodiment.

FIG. 15 is a cross-sectional side view of an illustrative self-mixingproximity sensor in accordance with an embodiment.

FIG. 16 is a circuit diagram of self-mixing proximity sensor circuitryin accordance with an embodiment.

FIGS. 17, 18, and 19 are side views of illustrative laser and photodiodeconfigurations for a self-mixing proximity sensor in accordance withembodiments.

FIG. 20 is a cross-sectional side view of an illustrative finger devicewith proximity sensors that measure distances to flexible membranes thatrest against side portions of a finger in accordance with an embodiment.

FIGS. 21, 22, 23, 24, and 25 are top views of illustrative fingerdevices with different numbers and locations of proximity sensors inaccordance with embodiments.

FIG. 26 is a perspective view of an illustrative finger device havingproximity sensors on opposing sides of a sidewall structure inaccordance with an embodiment.

FIG. 27 is a perspective view of an illustrative finger device havingproximity sensors located on sidewall structures in accordance with anembodiment.

FIG. 28 is a cross-sectional side view of an illustrative finger devicehaving proximity sensors on a upper portion of the finger device inaccordance with an embodiment.

FIG. 29 is a perspective view of an illustrative finger device havinghousing that covers most of the tip of the user's finger and havingproximity sensors in accordance with an embodiment.

FIG. 30 is a side view of an illustrative finger device having a sidehousing portion that extends down a back end of a fingertip and havingproximity sensors in accordance with an embodiment.

FIG. 31 is a side view of an illustrative finger device having a sidehousing portion that extends down a back end of a fingertip and havingproximity sensors at different heights along the side of the fingeraccordance with an embodiment.

FIG. 32 is a side view of an illustrative finger device having a sidehousing portion that curves away from a back end of a fingertip inaccordance with an embodiment.

FIG. 33 is a cross-sectional side view of an illustrative finger devicehaving a strap in accordance with an embodiment.

DETAILED DESCRIPTION

Electronic devices that are configured to be mounted on the body of auser may be used to gather user input and to provide a user with output.For example, electronic devices that are configured to be worn on one ormore of a user's fingers, which are sometimes referred to as fingerdevices or finger-mounted devices, may be used to gather user input andto supply output. A finger device may, as an example, include aninertial measurement unit with an accelerometer for gatheringinformation on finger motions such as finger taps or free-space fingergestures, may include proximity sensors such as self-mixinginterferometric optical proximity sensors for measuring small changes indistance to the finger surface as the finger moves, may include forcesensors for gathering information on normal and shear forces in thefinger device and the user's finger, and may include other sensors forgathering information on the interactions between the finger device (andthe user's finger on which the device is mounted) and the surroundingenvironment. The finger device may include a haptic output device toprovide the user's finger with haptic output and may include otheroutput components.

One or more finger devices may gather user input from a user. The usermay use finger devices in operating a virtual reality or mixed realitydevice (e.g., head-mounted equipment such as glasses, goggles, a helmet,or other device with a display) and/or in operating other equipment suchas desktop computers, laptop computers, tablet computers, and otherelectronic devices. During operation, the finger devices may gather userinput such as information on interactions between the finger device(s)and the surrounding environment (e.g., interactions between a user'sfingers and the environment, including finger motions and otherinteractions associated with virtual content displayed for a user). Theuser input may be used in controlling visual output on the display.Corresponding haptic output may be provided to the user's fingers usingthe finger devices. Haptic output may be used, for example, to providethe fingers of a user with a desired texture sensation as a user istouching a real object or as a user is touching a virtual object. Hapticoutput can also be used to create detents and other haptic effects.

Finger devices can be worn on any or all of a user's fingers (e.g., theindex finger, the index finger and thumb, three of a user's fingers onone of the user's hands, some or all fingers on both hands, etc.). Toenhance the sensitivity of a user's touch as the user interacts withsurrounding objects, finger devices may have inverted U shapes or otherconfigurations that allow the finger devices to be worn over the top andsides of a user's finger tips while leaving the user's finger padsexposed. This allows a user to touch objects with the finger padportions of the user's fingers during use. If desired, finger devicesmay be worn over knuckles on a user's finger, between knuckles, and/oron other portions of a user's finger. The use of finger devices on auser's finger tips is sometimes described herein as an example.

Users can use the finger devices to interact with any suitableelectronic equipment. For example, a user may use one or more fingerdevices to interact with a virtual reality or mixed reality system(e.g., a head-mounted device with a display), to supply input to adesktop computer, tablet computer, cellular telephone, watch, ear buds,or other accessory, or to interact with other electronic equipment.

FIG. 1 is a schematic diagram of an illustrative system of the type thatmay include one or more finger devices. As shown in FIG. 1 , system 8may include electronic device(s) such as finger device(s) 10 and otherelectronic device(s) 24. Each finger device 10 may be worn on a fingerof a user's hand. Additional electronic devices in system 8 such asdevices 24 may include devices such as a laptop computer, a computermonitor containing an embedded computer, a tablet computer, a desktopcomputer (e.g., a display on a stand with an integrated computerprocessor and other computer circuitry), a cellular telephone, a mediaplayer, or other handheld or portable electronic device, a smallerdevice such as a wristwatch device, a pendant device, a headphone orearpiece device, a head-mounted device such as glasses, goggles, ahelmet, or other equipment worn on a user's head, or other wearable orminiature device, a television, a computer display that does not containan embedded computer, a gaming device, a remote control, a navigationdevice, an embedded system such as a system in which equipment ismounted in a kiosk, in an automobile, airplane, or other vehicle, aremovable external case for electronic equipment, a strap, a wrist bandor head band, a removable cover for a device, a case or bag that hasstraps or that has other structures to receive and carry electronicequipment and other items, a necklace or arm band, a wallet, sleeve,pocket, or other structure into which electronic equipment or otheritems may be inserted, part of a chair, sofa, or other seating (e.g.,cushions or other seating structures), part of an item of clothing orother wearable item (e.g., a hat, belt, wrist band, headband, sock,glove, shirt, pants, etc.), or equipment that implements thefunctionality of two or more of these devices.

With one illustrative configuration, which may sometimes be describedherein as an example, device 10 is a finger-mounted device having afinger-mounted housing with a U-shaped body that grasps a user's fingeror a finger-mounted housing with other shapes configured to rest againsta user's finger and device(s) 24 is a cellular telephone, tabletcomputer, laptop computer, wristwatch device, head-mounted device, adevice with a speaker, or other electronic device (e.g., a device with adisplay, audio components, and/or other output components). A fingerdevice with a U-shaped housing may have opposing left and right sidesthat are configured to receive a user's finger and a top housing portionthat couples the left and right sides and that overlaps the user'sfingernail.

Devices 10 and 24 may include control circuitry 12 and 26. Controlcircuitry 12 and 26 may include storage and processing circuitry forsupporting the operation of system 8. The storage and processingcircuitry may include storage such as nonvolatile memory (e.g., flashmemory or other electrically-programmable-read-only memory configured toform a solid state drive), volatile memory (e.g., static or dynamicrandom-access-memory), etc. Processing circuitry in control circuitry 12and 26 may be used to gather input from sensors and other input devicesand may be used to control output devices. The processing circuitry maybe based on one or more microprocessors, microcontrollers, digitalsignal processors, baseband processors and other wireless communicationscircuits, power management units, audio chips, application specificintegrated circuits, etc.

To support communications between devices 10 and 24 and/or to supportcommunications between equipment in system 8 and external electronicequipment, control circuitry 12 may communicate using communicationscircuitry 14 and/or control circuitry 26 may communicate usingcommunications circuitry 28. Circuitry 14 and/or 28 may includeantennas, radio-frequency transceiver circuitry, and other wirelesscommunications circuitry and/or wired communications circuitry.Circuitry 14 and/or 26, which may sometimes be referred to as controlcircuitry and/or control and communications circuitry, may, for example,support bidirectional wireless communications between devices 10 and 24over wireless link 38 (e.g., a wireless local area network link, anear-field communications link, or other suitable wired or wirelesscommunications link (e.g., a Bluetooth® link, a WiFi® link, a 60 GHzlink or other millimeter wave link, etc.). Devices 10 and 24 may alsoinclude power circuits for transmitting and/or receiving wired and/orwireless power and may include batteries. In configurations in whichwireless power transfer is supported between devices 10 and 24, in-bandwireless communications may be supported using inductive power transfercoils (as an example).

Devices 10 and 24 may include input-output devices such as devices 16and 30. Input-output devices 16 and/or 30 may be used in gathering userinput, in gathering information on the environment surrounding the user,and/or in providing a user with output. Devices 16 may include sensors18 and devices 24 may include sensors 32. Sensors 18 and/or 32 mayinclude proximity sensors (e.g., self-mixing optical proximity sensors),force sensors (e.g., strain gauges, capacitive force sensors, resistiveforce sensors, etc.), audio sensors such as microphones, touch and/orproximity sensors such as capacitive sensors, optical sensors such asoptical sensors that emit and detect light, ultrasonic sensors (e.g.,ultrasonic sensors for tracking device orientation and location and/orfor detecting user input such as finger input), and/or other touchsensors and/or proximity sensors, monochromatic and color ambient lightsensors, image sensors, sensors for detecting position, orientation,and/or motion (e.g., accelerometers, magnetic sensors such as compasssensors, gyroscopes, and/or inertial measurement units that contain someor all of these sensors), muscle activity sensors (EMG) for detectingfinger actions, radio-frequency sensors, depth sensors (e.g., structuredlight sensors and/or depth sensors based on stereo imaging devices),optical sensors such as self-mixing sensors and light detection andranging (lidar) sensors that gather time-of-flight measurements, opticalsensors such as visual odometry sensors that gather position and/ororientation information using images gathered with digital image sensorsin cameras, gaze tracking sensors, visible light and/or infrared camerashaving digital image sensors, humidity sensors, moisture sensors, and/orother sensors. In some arrangements, devices 10 and/or 24 may usesensors 18 and/or 32 and/or other input-output devices 16 and/or 30 togather user input (e.g., buttons may be used to gather button pressinput, touch sensors overlapping displays can be used for gathering usertouch screen input, touch pads may be used in gathering touch input,microphones may be used for gathering audio input, accelerometers may beused in monitoring when a finger contacts an input surface and maytherefore be used to gather finger press input, etc.). If desired,device 10 and/or device 24 may include rotating buttons (e.g., a crownmechanism on a watch or finger device or other suitable rotary buttonthat rotates and that optionally can be depressed to select items ofinterest). Alphanumeric keys and/or other buttons may be included indevices 16 and/or 30. In some configurations, sensors 18 may includejoysticks, roller balls, optical sensors (e.g., lasers that emit lightand image sensors that track motion by monitoring and analyzingchangings in the speckle patterns and other information associated withsurfaces illuminated with the emitted light as device 10 is movedrelative to those surfaces), fingerprint sensors, and/or other sensingcircuitry. Radio-frequency tracking devices may be included in sensors18 to detect location, orientation, and/or range. Beacons (e.g.,radio-frequency beacons) may be used to emit radio-frequency signals atdifferent locations in a user's environment (e.g., at one or moreregistered locations in a user's home or office). Radio-frequency beaconsignals can be analyzed by devices 10 and/or 24 to help determine thelocation and position of devices 10 and/or 24 relative to the beacons.If desired, devices 10 and/or 24 may include beacons. Frequency strength(received signal strength information), beacon orientation,time-of-flight information, and/or other radio-frequency information maybe used in determining orientation and position information. At somefrequencies (e.g., lower frequencies such as frequencies below 10 GHz),signal strength information may be used, whereas at other frequencies(e.g., higher frequencies such as frequencies above 10 GHz), indoorradar schemes may be used). If desired, light-based beacons, ultrasonicbeacons, and/or other beacon devices may be used in system 8 in additionto or instead of using radio-frequency beacons and/or radio-frequencyradar technology.

Devices 16 and/or 30 may include haptic output devices 20 and/or 34.Haptic output devices 20 and/or 34 can produce motion that is sensed bythe user (e.g., through the user's fingertips). Haptic output devices 20and/or 34 may include actuators such as electromagnetic actuators,motors, piezoelectric actuators, electroactive polymer actuators,vibrators, linear actuators (e.g., linear resonant actuators),rotational actuators, actuators that bend bendable members, actuatordevices that create and/or control repulsive and/or attractive forcesbetween devices 10 and/or 24 (e.g., components for creatingelectrostatic repulsion and/or attraction such as electrodes, componentsfor producing ultrasonic output such as ultrasonic transducers,components for producing magnetic interactions such as electromagnetsfor producing direct-current and/or alternating-current magnetic fields,permanent magnets, magnetic materials such as iron or ferrite, and/orother circuitry for producing repulsive and/or attractive forces betweendevices 10 and/or 24). In some situations, actuators for creating forcesin device 10 may be used in squeezing a user's finger and/or otherwisedirectly interacting with a user's finger pulp. In other situations,these components may be used to interact with each other (e.g., bycreating a dynamically adjustable electromagnetic repulsion and/orattraction force between a pair of devices 10 and/or between device(s)10 and device(s) 24 using electromagnets).

If desired, input-output devices 16 and/or 30 may include other devices22 and/or 36 such as displays (e.g., in device 24 to display images fora user), status indicator lights (e.g., a light-emitting diode in device10 and/or 24 that serves as a power indicator, and other light-basedoutput devices), speakers and other audio output devices,electromagnets, permanent magnets, structures formed from magneticmaterial (e.g., iron bars or other ferromagnetic members that areattracted to magnets such as electromagnets and/or permanent magnets),batteries, etc. Devices 10 and/or 24 may also include power transmittingand/or receiving circuits configured to transmit and/or receive wiredand/or wireless power signals.

FIG. 2 is a top view of a user's finger (finger 40) and an illustrativefinger-mounted device 10. As shown in FIG. 2 , device 10 may be formedfrom a finger-mounted unit that is mounted on or near the tip of finger40 (e.g., partly or completely overlapping fingernail 42). If desired,device 10 may be worn elsewhere on a user's fingers such as over aknuckle, between knuckles, etc. Configurations in which a device such asdevice 10 is worn between fingers 40 may also be used.

A user may wear one or more of devices 10 simultaneously. For example, auser may wear a single one of devices 10 on the user's ring finger orindex finger. As another example, a user may wear a first device 10 onthe user's thumb, a second device 10 on the user's index finger, and anoptional third device 10 on the user's middle finger. Arrangements inwhich devices 10 are worn on other fingers and/or all fingers of one orboth hands of a user may also be used.

Control circuitry 12 (and, if desired, communications circuitry 14and/or input-output devices 16) may be contained entirely within device10 (e.g., in a housing for a fingertip-mounted unit) and/or may includecircuitry that is coupled to a fingertip structure (e.g., by wires froman associated wrist band, glove, fingerless glove, etc.). Configurationsin which devices 10 have bodies that are mounted on individual userfingertips are sometimes described herein as an example.

FIG. 3 is a cross-sectional side view of an illustrative finger device(finger-mounted device) 10 showing illustrative mounting locations 46for electrical components (e.g., control circuitry 12, communicationscircuitry 14, and/or input-output devices 16 such as sensors 18, hapticoutput devices 20, and/or other devices 22) within and/or on thesurface(s) of finger device housing 44. These components may, ifdesired, be incorporated into other portions of housing 44.

As shown in FIG. 3 , housing 44 may have a U shape (e.g., housing 44 maybe a U-shaped housing structure that faces downwardly and covers theupper surface of the tip of user finger 40 and fingernail 42). Duringoperation, a user may press against structures such as structure 50. Asthe bottom of finger 40 (e.g., finger pulp 40P) presses against surface48 of structure 50, the user's finger may compress and force portions ofthe finger outwardly against the sidewall portions of housing 44 (e.g.,for sensing by force sensors or other sensors mounted to the sideportions of housing 44). Lateral movement of finger 40 in the X-Y planemay also be sensed using force sensors or other sensors on the sidewallsof housing 44 or other portions of housing 44 (e.g., because lateralmovement will tend to press portions of finger 40 against some sensorsmore than others and/or will create shear forces that are measured byforce sensors that are configured to sense shear forces).

Ultrasonic sensors, optical sensors, inertial measurement units, straingauges and other force sensors, radio-frequency sensors, and/or othersensors may be used in gathering sensor measurements indicative of theactivities of finger 40. If desired, these sensors may also be used inmapping the contours of three-dimensional objects (e.g., bytime-of-flight measurements and/or other measurements). For example, anultrasonic sensor such as a two-dimensional image sensor or anultrasonic sensor with a single ultrasonic transducer element may emitfree-space ultrasonic sound signals that are received and processedafter reflecting off of external objects. This allows athree-dimensional ultrasonic map to be generated indicating the shapesand locations of the external objects.

In some configurations, finger activity information (position, movement,orientation, etc.) may be gathered using sensors that are mounted inexternal electronic equipment (e.g., in a computer or other desktopdevice, in a head-mounted device or other wearable device, and/or inother electronic device 24 that is separate from device 10). Forexample, optical sensors such as images sensors that are separate fromdevices 10 may be used in monitoring devices 10 to determine theirposition, movement, and/or orientation. If desired, devices 10 mayinclude passive and/or active optical registration features to assist animage sensor in device 24 in tracking the position, orientation, and/ormotion of device 10. For example, devices 10 may include light-emittingdevices such as light-emitting diodes and/or lasers. The light-emittingdevices may include light-emitting diodes, lasers (e.g., laser diodes,vertical cavity surface-emitting lasers, etc.), or other light sourcesand may operate at visible wavelengths, ultraviolet wavelengths, and/orinfrared wavelengths. The light-emitting devices may be arranged in anasymmetric pattern on housing 44 and may emit light that is detected byan image sensor, depth sensor, and/or other light-based tracking sensorcircuitry in device 24 (e.g., a head-mounted device, desktop computer,stand-alone camera-based monitoring systems, and/or other electricalequipment with an image sensor or other tracking sensor circuitry). Byprocessing the received patterned of emitted light, device 24 candetermine the position, orientation, and/or motion of device 10. Ifdesired, the light-emitting devices can be removable and/or customizable(e.g., a user can customize the location and type of light-emittingdevices).

Tracking can also be performed that involves extrapolating from a knownbody part orientation (e.g., a finger orientation) to produceorientation information on other body parts (e.g., wrist and/or armorientation estimated using inverse kinematics). Visual odometry sensorsmay, if desired, be included in devices 10. These sensors may includeimage sensors that gather frames of image data of the surroundings ofdevices 10 and may be used in measuring position, orientation, and/ormotion from the frame of image data. Lidar, ultrasonic sensors orientedin multiple directions, radio-frequency tracking sensors, and/or otherfinger device tracking arrangements may be used, if desired. In somearrangements, user input for controlling system 8 can include both userfinger input and other user input (e.g., user eye gaze input, user voiceinput, etc.). For example, gaze tracking information such as a user'spoint-of-gaze measured with a gaze tracker can be fused with fingerinput when controlling device 10 and/or devices 24 in system 8. A usermay, for example, gaze at an object of interest while device 10 usingone or more of sensors 18 (e.g., an accelerometer, force sensor, touchsensor, etc.) to gather information such as tap input (movement ofdevice 10 resulting in measurable forces and/or accelerometer outputwhen device 10 strikes a table top or other external surface),double-tap input, force input, multi-finger gestures (taps, swipes,and/or other gestures on external surfaces and/or the housing surfacesof multiple devices 10), drag and drop operations associated withobjects selected using a lingering gaze or other point-of-gaze input,etc. The finger input may include information on finger orientation,position, and/or motion and may include information on how forcefully afinger is pressing against surfaces (e.g., force information). Fingerpointing input (e.g., the direction of finger pointing) may be gatheredusing radio-frequency sensors among sensors 18 and/or other sensors indevice(s) 10.

If desired, user input may include air gestures (sometimes referred toas three-dimensional gestures or non-contact gestures) gathered withsensors 18 (e.g., proximity sensors, image sensors, ultrasonic sensors,radio-frequency sensors, etc.). Air gestures (e.g., non-contact gesturesin which a user's fingers hover and/or move relative to the sensors 18of device 10 and/or in which device 10 hovers and/or moves relative toexternal surfaces) and/or touch and/or force-based input may includemultifinger gestures (e.g., pinch to zoom, etc.). In some embodiments, auser may wear multiple devices 10 (e.g., on a thumb and index finger)and these devices may be used to gather finger pinch input such as pinchclick gesture input or pinch force input. For example, a pinch clickinput may be detected when a tap (e.g., a peak in an accelerometeroutput signal) for a thumb device correlates with a tap for an indexfinger device and/or pinch force input may be gathered by measuringstrain gauge output with strain gauges in devices 10 as the devices 10press against each other. Pinch force can also be detected by measuringthe size of the contact patch produced when a finger presses against atwo-dimensional touch sensor (larger contact area being associated withlarger applied force). As another example, pinch input and/or otherfinger gestures that involve contact with the finger pad may be detectedusing a proximity sensor that measures small changes in distance to thefinger as the finger pad is moved (e.g., as the finger pad of a pointerfinger is moved around by a thumb finger and/or moved around by asurface as the finger pad makes contact with the surface).

By correlating user input from a first of devices 10 with user inputfrom a second of devices 10 and/or by otherwise analyzing finger devicesensor input, pinch gestures (e.g., pinch click or pinch tap gesturesand/or pinch force input) and other multi-device input may be detectedand used in manipulating virtual objects or taking other actions insystem 8. Consider, as an example, the use of a pinch gesture to selecta virtual object associated with a user's current point-of-gaze. Oncethe virtual object has been selected based on the direction of theuser's point-of-gaze (or finger point direction input) and based on thepinch gesture input or other user input, further user input gatheredwith one or more devices 10 may be used to rotate and/or otherwisemanipulate the virtual object. For example, information on fingermovement (e.g., rotational movement) may be gathered using an internalmeasurement unit or other sensor 18 in device(s) 10 and this rotationalinput used to rotate the selected object. In some scenarios, an objectmay be selected based on point-of-gaze (e.g., when a user'spoint-of-gaze is detected as being directed toward the object) and,following selection, object attributes (e.g., virtual object attributessuch as virtual object appearance and/or real-world object attributessuch as the operating settings of a real-world device) can be adjustedusing strain gauge or touch sensor contact patch pinch input (e.g.,detected pinch force between finger devices 10 that are being pinchedtogether on opposing fingers) and/or can be adjusted using finger deviceorientation input (e.g., to rotate a virtual object, etc.).

If desired, gestures such as air gestures (three-dimensional gestures)may involve additional input. For example, a user may control system 8using hybrid gestures that involve movement of device(s) 10 through theair (e.g., an air gesture component) and that also involve contact (and,if desired, movement) of a thumb or other finger against atwo-dimensional touch sensor, force sensor, or other sensor 18. As anexample, an inertial measurement unit may detect user movement of finger40 through the air (e.g., to trace out a path) while detecting forceinput, touch input, or other input (e.g., finger pinch input or otherinput to adjust a line or other virtual object that is being drawn alongthe path).

The sensors in device 10 may, for example, measure how forcefully a useris moving device 10 (and finger 40) against surface 48 (e.g., in adirection parallel to the surface normal n of surface 48 such as the −Zdirection of FIG. 3 ) and/or how forcefully a user is moving device 10(and finger 40) within the X-Y plane, tangential to surface 48. Thedirection of movement of device 10 in the X-Y plane and/or in the Zdirection can also be measured by the force sensors and/or other sensors18 at locations 46.

Structure 50 may be a portion of a housing of device 24, may be aportion of another device 10 (e.g., another housing 44), may be aportion of a user's finger 40 or other body part, may be a surface of areal-world object such as a table, a movable real-world object such as abottle or pen, or other inanimate object external to device 10, and/ormay be any other structure that the user can contact with finger 40while moving finger 40 in a desired direction with a desired force.Because motions such as these can be sensed by device 10, device(s) 10can be used to gather pointing input (e.g., input moving a cursor orother virtual object on a display such as a display in devices 36), canbe used to gather tap input, swipe input, pinch-to-zoom input (e.g.,when a pair of devices 10 is used), or other gesture input (e.g., fingergestures, hand gestures, arm motions, etc.), and/or can be used togather other user input.

FIG. 4 is a top view of an illustrative finger device on a finger of auser. In the illustrative configuration of FIG. 4 , device 10 includesone or more proximity sensors such as proximity sensors 52. Proximitysensors 52 (sometimes referred to as distance sensors or displacementsensors) may each be configured to measure a distance D between finger40 and proximity sensor 52. The distances between finger 40 and sensors52 may change as the user moves finger 40 in the air, touches finger 40on a surface, and/or touches finger 40 with another finger. Based on thedistance changes recorded by each sensor 52, control circuitry 12 maydetermine how finger 40 is moving and may take corresponding action. Forexample, control circuitry 12 may send control signals to one or moreelectronic devices (e.g., device 24 of FIG. 1 ) in response to thefinger movements measured by sensors 52.

Proximity sensors in device 10 such as sensors 52 may be optical sensors(e.g., having a light source and a light detector), ultrasonic sensors(e.g., having a ultrasonic transducer and a corresponding detector),magnetic sensors, capacitive sensors, pressure sensors, and/or othersensors configured to gather information on the distance D betweenfinger 40 and sensors 52. Arrangements in which sensors 52 are based onpiezoelectric materials or based on mechanical switches may also beused, if desired.

In one illustrative arrangement, which may sometimes be described hereinas an example, proximity sensors 52 (sometimes referred to as distancesensors or displacement sensors) may include self-mixing interferometricproximity sensors (sometimes referred to as self-mixing opticalproximity sensors, self-mixing proximity sensors, self-mixinginterferometers, etc.). A self-mixing proximity sensor may have acoherent or partially coherent source of electromagnetic radiation. Thesource of radiation may, for example, be a coherent light source such asan infrared vertical cavity surface-emitting laser, a quantum cascadelaser, or other laser. The self-mixing proximity sensor may also have alight detector such as a photodiode and/or otherelectromagnetic-radiation-sensitive element.

Self-mixing proximity sensors may have submicron resolution and may beconfigured to detect very small changes in distance. This allows sensors52 to detect very small movements of finger 40 (sometimes referred to asmicrogestures or nanogestures). If desired, the optical axis of eachsensor 52 may be angled towards a center region of the finger pad toincrease sensor sensitivity to finger displacements that result from thefinger pad contacting an external surface or another finger.

FIGS. 5, 6, 7, 8, 9, 10, 11, 12, 13, and 14 show illustrative examplesof user input that may be detected with proximity sensors 52 in device10 such as self-mixing optical proximity sensors.

In the example of FIG. 5 , finger device 10 is being used to detectfinger input to the finger pulp. In particular, one or more proximitysensors 52 in device 10 may measure changes in distance between sensors52 and finger 40-1 (e.g., a pointer finger or other suitable fingerwearing device 10) as finger 40-2 (e.g., a thumb or other suitablefinger) makes contact with finger pulp 40P of finger 40-1. Sensors 52may detect lateral movement of finger pulp 40 in which pulp 40P movesrelative to finger 40-2 and may also detect movement of finger pulp 40Pwith little or no actual movement of pulp 40P relative to finger 40-2.For example, the user may use finger 40-2 to move finger pulp 40P around(e.g., from side-to-side, from front-to back, from back-to-front, or anyother suitable direction) without actually sliding finger 40-2 acrossfinger pulp 40P. Because this movement of finger pulp 40P somewhatresembles the movement of a joystick, this type of input may sometimesbe referred to as joystick input. Sensors 52 may also detect taps andpinches between fingers 40-1 and 40-2, since such movements will pushthe sides of finger 40-1 outward towards sensors 52 and will thereforeresult in corresponding changes in distance between the sides of finger40-1 and sensors 52.

FIG. 6 shows an example in which finger device 10 is being used todetect finger input on a surface of structure 50. In particular, one ormore proximity sensors 52 in device 10 may measure changes in distancebetween sensors 52 and finger 40 (e.g., a pointer finger or othersuitable finger wearing device 10) as finger 40 makes contact withstructure 50. Sensors 52 may detect lateral movement of finger pulp 40Pin which pulp 40P moves relative to structure 50 and may also detectmovement of finger pulp 40P with little or no actual movement of pulp40P relative to structure 50. For example, the user may move finger pulp40P around on structure 50 (e.g., from side-to-side, from front-to back,from back-to-front, or any other suitable direction) without actuallysliding finger 40 across structure 50. Because this movement of fingerpulp 40P somewhat resembles the movement of a joystick, this type ofinput may sometimes be referred to as joystick input. Sensors 52 mayalso detect taps and presses of finger 40 on structure 50, since suchmovements will push the sides of finger 40-1 outward towards sensors 52and will therefore result in corresponding changes in distance betweenthe sides of finger 40-1 and sensors 52.

FIGS. 7, 8, and 9 show illustrative movements of finger pulp 40P thatmay be detected using distance sensors such as proximity sensors 52. Forsimplicity, device 10 is not shown in these figures, but it should beunderstood that device 10 may be mounted on top of finger 40 and mayhave one or more proximity sensors such as sensors 52 that measuredistance changes between finger 40 and sensors 52 as finger pulp 40Pmoves around (e.g., as finger pulp 40P is moved around by another fingersuch as a user's thumb as shown in FIG. 5 and/or as finger pulp 40P ismoved around by a surface as shown in FIG. 6 ).

In the example of FIG. 7 , finger pulp 40P of finger 40 is being movedto the left in direction 60. This movement may be a result of the usermoving finger 40 (and/or applying shear force) on a surface to the rightin direction 54, or this may be a result of a user pushing finger pulp40P to the left in direction 60 with another finger (e.g., a thumbfinger or other suitable finger). The movement of finger pulp 40P indirection 60 results in distance change D1 on the right side of finger40 and distance change D2 on the left side of finger 40. D1 representsthe distance traveled by the right side portion of finger 40 as finger40 moves in direction 60, and D2 represents the distance traveled by theleft side portion of finger 40 as finger 40 moves in direction 60.

In the example of FIG. 8 , finger pulp 40P of finger 40 is being moveddiagonally in direction 62. This movement may be a result of the usermoving finger 40 (and/or applying shear force) on a surface in direction56, or this may be a result of a user pushing finger pulp 40P indirection 62 with another finger (e.g., a thumb finger or other suitablefinger). The movement of finger pulp 40P in direction 62 results indistance change D3 on the end of finger 40 and distance change D4 on theright side of finger 40. D3 represents the distance traveled by the end(e.g., the tip) of finger 40 as finger 40 moves in direction 62, and D4represents the distance traveled by the right side of finger 40 asfinger 40 moves in direction 62.

In the example of FIG. 9 , finger pulp 40P of finger 40 is being movedforward in direction 64. This movement may be a result of the usermoving finger 40 (and/or applying shear force) on a surface in direction58, or this may be a result of a user pushing finger pulp 40P indirection 64 with another finger (e.g., a thumb finger or other suitablefinger). The movement of finger pulp 40P in direction 64 results indistance change D5 on the end of finger 40. D5 represents the distancetraveled by the end (e.g., the tip) of finger 40 as finger 40 moves indirection 64.

The examples of FIGS. 7, 8, and 9 are merely illustrative examples ofthe types of finger movements that may be detected using one or moreproximity sensors 52 in device 10. Proximity sensors 52 may beconfigured to detect taps, presses, pinches, and/or other suitablefinger gestures by measuring the small changes in distance betweenfinger 40 and sensor(s) 52 that result from such finger gestures.Sensors 52 may include any suitable number of sensors at any suitablelocation on device 10 (e.g., one or more sensors 52 may be located onthe right side of finger 40, may be located on the left side of finger40, may be located on the tip of finger 40, may be located on top of thefingernail of finger 40, and/or may be located in other positionsrelative to finger 40). If desired, displacement data from multiplesensors 52 may be compared to determine precisely the amount anddirection with which finger 40 (e.g., finger pulp 40P) moves in responseto finger gestures made with the finger wearing device 10.

In addition to detecting movement of finger pulp 40P, sensors 52 may beused to detect other finger gestures that result in changes in distancebetween finger 40 and sensors 52. FIGS. 10, 11, 12, 13, and 14 areillustrative examples of other types of finger gestures that may bedetected using proximity sensors 52 (e.g., optical proximity sensorssuch as self-mixing optical proximity sensors and/or other proximitysensors that can measure changes in the position of finger 40).

FIG. 10 is an example in which device 10 is being used to detect theproximity of one or more adjacent fingers. In particular, device 10 maybe worn on finger 40-1 (e.g., a pointer finger or other suitable finger)and may detect activities of finger 40-2 (e.g., a middle finger or othersuitable finger) as it makes contact with and/or as it comes inproximity to device 10. For example, sensor 52 may detect a decrease indistance between sensor 52 and finger 40-1 as finger 40-2 makes contactwith finger 40-1 (and/or makes contact with device 10 on finger 40-1).Detecting when finger 40-2 is in contact with or close proximity tofinger 40-1 may be used to provide a different type of input than thatassociated with a single finger. For example, finger gestures made withtwo side-by-side fingers as shown in FIG. 10 may be used to scrollcontent on a display whereas finger gestures made with a single fingermay be used to move a cursor on a display, if desired.

FIG. 11 shows an example in which finger device 10 is being used todetect finger input on device 10. In particular, device 10 may be wornon finger 40-1 (e.g., a pointer finger or other suitable finger) and maydetect activities of finger 40-2 (e.g., a thumb or other suitablefinger) as it makes contact with and/or as it comes in proximity todevice 10. For example, proximity sensor 52 may measure a change indistance between sensor 52 and finger 40-1 as finger 40-2 contacts theexterior surface of device 10. In this way, sensors 52 can detectswipes, pinches, taps, presses, press-and-holds, or other gestures ondevice 10.

FIG. 12 shows an example in which finger device 10 is being used todetect finger input on top of device 10. In particular, device 10 may beworn on finger 40-1 (e.g., a pointer finger or other suitable finger)and may detect activities of finger 40-2 (e.g., a middle finger or othersuitable finger) as it makes contact with the upper surface of device10. For example, proximity sensor 52 may measure a change in distancebetween sensor 52 and finger 40-1 as finger 40-2 contacts the uppersurface of device 10. Sensor 52 may measure changes in the position ofthe top of finger 40-1 relative to sensor 52 (e.g., changes in theposition of the fingernail relative to sensor 52) and/or may measurechanges in position of one or more sides of finger 40-1 relative tosensor 52 as finger 40-2 contacts the top of finger 40-1 (and/or the topof device 10). In this way, sensors 52 can detect finger gestures on theupper surface of device 10.

FIG. 13 is an example showing how device 10 may be used to turn anobject into an input device. In the example of FIG. 13 , object 68 maybe a pen or pencil that does not contain any circuitry. A user wearingone or more finger devices 10 may rotate object 68 about itslongitudinal axis, may move the tip of object 68 across a surface (e.g.,surface 48 of structure 50 of FIG. 3 ), and/or may tap or press the tipof object 68 on a surface, and/or may make other movements of object 68.During movement of object 68, proximity sensors 52 in device 10 maydetect small changes in distance between finger 40 and sensors 52, whichin turn can be used to determine the location, orientation, and movementof object 68.

FIG. 14 shows an example in which finger device 10 is being used todetect a curling motion of finger 40. In particular, device 10 may beworn on finger 40 (e.g., a pointer finger or other suitable finger) andmay detect movement of the tip of finger 40 relative to the base offinger 40. As the tip of finger 40 curls in direction 72, the sides offinger 40 may be pushed outward, resulting in small changes in distancebetween proximity sensors 52 and finger 40. By measuring these smallchanges in distance with sensor(s) 52, device 10 can measure theposition of the tip of finger 40 as it moves relative to the base offinger 40.

If desired, the finger gestures of FIGS. 5-14 may be combined with oneanother and/or combined with other finger gestures to provide differenttypes of user input to an electronic device. As an example, a user mayselect an item on a display in device 24 by tapping finger 40 on asurface (as shown in the example of FIG. 6 ) and, once the item has beenselected, the user may manipulate the selected item by moving fingerpulp 40P with a thumb like one would move a joystick (e.g., as shown inFIG. 5 ). Multi-finger gestures may be detected by detecting an adjacentfinger as the user pinches against the finger pulp of a finger wearingdevice 10, by detecting an adjacent finger as the user presses a fingerwearing device 10 against a surface, by detecting an adjacent finger asthe user touches the outside of device 10, etc.

FIG. 15 is a diagram of an illustrative self-mixing proximity sensor(sometimes referred to as a self-mixing sensor or proximity sensor) andan associated target. As shown in FIG. 15 , self-mixing proximity sensor52 may include a laser such as vertical cavity surface emitting laser 74(e.g., self-mixing proximity sensor 52 may be a coherent self-mixingsensor having a diode laser or other coherent or partially coherentsource of light or other electromagnetic radiation). Laser 74 may havethin-film interference filter mirrors 90 (sometimes referred to as Braggreflectors) each of which is formed from a stack of thin-film layers ofalternating index of refraction. Active region 94 may be formed betweenmirrors 90. The lower mirror in laser 74 may have a nominal reflectivityof 100% or, in configurations such as bottom-emitting configurations,may have a nominal reflectivity of less than 100%. In some cases, thelaser can emit from both the top and bottom. This is particularly usefulif the laser is sitting above a photodetector. The upper mirror in laser74 may have a slightly lower reflectivity, so that laser 74 emits light86 towards target 82. Laser 74 may be controlled by applying a drivesignal to terminals 92 using control circuitry 12 (e.g., a drive circuitin circuitry 12). Sensing circuitry in circuitry 12 can measure thelight output of laser 74.

Emitted light 86 may have a wavelength of 850 nm or other suitablewavelength (e.g., a visible wavelength, an ultraviolet wavelength, aninfrared wavelength, a near-infrared wavelength, etc.). Target 82 maybe, for example, part of the user's finger (e.g., the side portions ofthe user's finger near the fingernail) and/or may be a flexible membranein device 10 that rests against the user's finger and that moves inresponse to movement of the finger. When emitted light 86 illuminatestarget 82, some of emitted light 86 will be reflected backwards towardsproximity sensor 52. Proximity sensor 52 may include a light sensitiveelement (e.g., a light detector) such as photodiode 76 (e.g., a resonantcavity photodetector or other suitable light detector). Terminals 96 ofphotodiode 76 may be coupled to sensing circuitry in control circuitry12. This circuitry gathers photodiode output signals that are producedin response to reception of reflected light 88. In addition to using aphotodiode, self-mixing can be detected using laser junction voltagemeasurements (e.g., if the laser is driven at a constant bias current)or laser bias current (e.g., if the laser is driven at a constantvoltage). A protective cover such as protective structure 80 may, ifdesired, be mounted over laser 74 and photodiode 76. Protectivestructure 80 may be transparent (or may have transparent portions). Ifdesired, a lens element such as lens element 102 may be incorporatedinto or attached to structure 80 to help direct light to target 82 andincrease the signal-to-noise ratio of proximity sensor 52.

Target 82 is located at a distance P1 from proximity sensor 52.Proximity sensor 52 may have a height P2 and a width P3. Height P2 maybe between 0.5 mm and 1 mm, between 1 mm and 2 mm, between 0.1 mm and0.5 mm, between 1 mm and 5 mm, less than 3 mm, greater than 3 mm, orother suitable height. Width P3 may be between 0.5 mm and 1 mm, between1 mm and 2 mm, between 0.1 mm and 0.5 mm, between 1 mm and 5 mm, lessthan 2 mm, greater than 2 mm, or other suitable width.

Some of light 88 that is reflected or backscattered from target 82reenters the laser cavity of laser 74 and perturbs the electric fieldcoherently, which also reflects as a perturbation to the carrier densityin laser 74. These perturbations in laser 74 causes coherent self-mixingfluctuations in the power of emitted light 86 and associated operatingcharacteristics of laser 74 such as laser junction voltage and/or laserbias current. These fluctuations may be monitored. For example, thefluctuations in the power of light 86 may be monitored using photodiode76. In the example of FIG. 15 , photodiode 74 and laser 76 are formedadjacent to each other on the upper surface of substrate 78.

As shown in FIG. 16 , control circuitry 12 includes circuitry forimplementing a driver for laser 74 (drive circuit 12-1) and circuitryfor implementing a sensing circuit for photodiode 76 (sense circuit12-2). Drive circuit 12-1 is used in applying a modulated drive currentId to laser 74. Sense circuit 12-2 is used in gathering signals PDoutfrom photodiode 76 that are processed by control circuitry 12 or outputsignals may be gathered using junction voltage or bias currentmeasurements.

A modulation scheme is used for driving laser 74 for the purpose ofinducing a wavelength modulation, and a photodiode signal processingscheme or junction voltage or bias current processing scheme is used inprocessing the measured self-mixing fluctuations in output power to thatallow control circuitry 12 to determine the distance P1 betweenproximity sensor 52 and target 82 in accordance with the principles ofself-mixing interferometry.

A modulation scheme for driving laser 74 may, for example, use asinusoidal wave drive signal, a triangular wave drive signal, and/orother suitable drive signal that, due to the dependence of outputwavelength on drive current magnitude of laser 74, continuously variesthe wavelength of light 86. The wavelength variations of light 86 causethe self-mixing interference signal of laser 74 to exhibit ripples. Theprocessing scheme used on the photodiode signal can extract informationfrom these ripples, from which distance P1 may be calculated. DistanceP1 may, for example, be determined within less than 1 micron accuracy,less than 0.2 mm accuracy, less than 0.15 mm accuracy, less than 0.1 mmaccuracy, less than 0.01 mm accuracy, or other suitable accuracy. Due tothis high accuracy, measurements of extremely small changes in theposition of finger 40 can be made with a high confidence.

The example of FIG. 15 in which laser 74 and photodiode 76 are formedside-by-side on substrate 78 is merely illustrative. Other arrangementsmay be used, if desired. For example, photodiode 76 may be formed orbonded under laser 74, may be monolithically integrated into laser 74,or may be formed or bonded on top of laser 74. In the example of FIG. 17, photodiode 76 is an integrated monolithic photodiode that is formedunder laser 74. If desired, photodiode 76 may be an intra-cavityphotodiode that is located in the cavity of laser 74 (e.g., betweenreflectors 92 of FIG. 15 ).

In the example of FIG. 18 , photodiode 76 is an integrated monolithicphotodiode having a ring-shape that surrounds laser 74. Laser 74 mayhave a corresponding ring-shaped portion 74-1 that surrounds an innerportion 74-2. If desired, inner portion 74-2 may be forward biased andouter ring-shaped portion 74-1 may be reverse biased. Inner portion 74-2may emit light 86. If desired, a beam splitter such as beam splitter 98may be placed between portion 74-2 of laser 74 and target 82.

In the example of FIG. 19 , laser 74 has been coupled to a separatephotodiode 76 using coupling structures 100 (e.g., solder bumps, epoxy,adhesive, etc.). If desired, laser 74 may emit light 86 from the top andbottom of laser 74. The top-emitted light 86 may be directed to target82 and the bottom emitted light may be absorbed by photodiode 76.

FIG. 20 is a cross-sectional side view of an illustrative finger devicewith proximity sensors 52. As shown in FIG. 20 , optical proximitysensors may be separated from target 82 by cavity 116. Cavity 116 may befilled with air, fluid, and/or other suitable material through whichoptical signals associated with proximity sensor 52 may pass as lightpasses from sensor 52 to target 82 and from target 82 to sensor 52. Inthe example of FIG. 20 , target 82 is a flexible membrane (e.g., aflexible layer of silicone, polymer, or other material) that restsagainst the sides of finger 40. As finger 40 moves, the distance betweenmembrane 82 and sensor 52 (e.g., distance P1 of FIG. 15 ) may change.These changes in distance between membrane 82 and sensor 52 may bemeasured to thereby detect movements of different portions of finger 40(e.g., micromovements associated with the finger gestures described inconnection with FIGS. 3-14 ).

The use of optical proximity sensors for sensors 52 is merelyillustrative. Proximity sensors in device 10 such as sensors 52 may beultrasonic sensors (e.g., having a ultrasonic transducer and acorresponding detector), magnetic sensors, capacitive sensors, pressuresensors, and/or other sensors configured to gather information on thelocation and movement of finger 40.

If desired, proximity sensor 52 may include a pressure sensor (e.g., inaddition to or instead of an optical distance sensor) in cavity 116 thatmeasures barometric pressure changes as membrane 82 moves in response tofinger movement. Arrangements in which membrane 82 incorporates one ormore force sensors may also be used. For example, membrane 82 mayinclude a strain gauge for measuring force and/or may include acapacitive electrode that is used to measure force (e.g., by detecting achange in distance between the electrode on membrane 82 and an electrodein sensor 52).

FIGS. 21, 22, 23, 24, and 25 show illustrative locations and numbers ofproximity sensors 52 in device 10. In the example of FIG. 21 , a singleproximity sensor 52 is located on the left side of finger 40, and asingle proximity sensor 52 is located on the right side of finger 40. Ifdesired, the sensors may not be directly opposite one another (e.g., onesensor 52 may be closer to the tip of finger 40 than the other sensor 52so that data from the two sensors 52 can be compared to detectfront-to-back movements as well as side-to-side movements).

In the example of FIG. 22 , two sensors 52 are located only on one sideof device 10. The data from the two sensors 52 may be compared to detectfront-to-back movements as well as side-to-side movements.

In the example of FIG. 23 , two sensors 52 are located on the left sideof device 10, and one sensor 52 is located on the right side of device10. The data from sensors 52 may be compared to detect front-to-backmovements as well as side-to-side movements.

FIGS. 24 and 25 show illustrative examples in which device 10 includessensors 52 on the sides and the tip of the user's finger. In the exampleof FIG. 24 , device 10 does not cover the user's fingernail. In the FIG.25 example, the fingernail is covered by device 10. The examples ofFIGS. 21-25 are merely illustrative. There may be one, two, three, four,five, six, ten, more than ten, or less than ten sensors 52 in device 10mounted in any suitable location of device 10.

FIGS. 26, 27, 28, 29, 30, and 31 are diagrams of device 10 showingillustrative locations of sensors 52. As shown in FIG. 26 , device 10may include first and second housing portions 108 coupled by hinge 104.Hinge 104 may allow housing portions 108 to be moved towards or awayfrom each other to accommodate fingers of different sizes. Each housingportion 108 may have a sidewall portion such as sidewall portion 106that extends down a side portion of the user's finger. In the example ofFIG. 26 , proximity sensors 52 are located on opposing sides of sidewallportion 106. FIG. 27 shows an example in which proximity sensors 52 arelocated on sidewall portion 106 itself.

FIG. 28 shows an example in which sensors 52 are located in an upperportion of device 10 (e.g., in housing portions 108) so that sensors 52rest on the user's fingernail 42.

In the example of FIG. 29 , device 10 has a thimble shape with anopening 114 for receiving the user's finger. The user may insert his orher finger in opening 114 in direction 112. Device 10 may have anadditional opening such as opening 110 that exposes the finger pad ofthe finger. Since device 10 has a finger glove shape that covers most ofthe tip of the user's finger, sensors 52 may be located below the user'sfinger (adjacent to the finger pad which is exposed through opening110), on the sides of the user's finger, on top of the user's finger, atthe tip of the user's finger, and/or in any other suitable location ofdevice 10.

FIG. 30 shows an example in which sidewall portion 106 extends down aback end of the tip of finger 40 (e.g., closer to the joint between thedistal phalanx and the middle phalanx). This provides additional realestate along the side portions of the fingertip for sensors 52. Inparticular, sensors 52 may be mounted in side housing portion 106P. Sidehousing portion 106P may be formed from the same or different materialas side housing portion 106. If desired, side housing portion 106P maybe formed from a softer and/or more flexible material than side housingportion 106. For example, side housing portion 106 may be rigid toprovide the desired clamping force to hold device 10 on finger 40, whileside housing portion 106P may be flexible so that finger movements willcause corresponding deformations in housing 106P (e.g., in membrane 82in housing 106P) that can be detected by sensors 52.

Sensors 52 may be located at the same height of the side portion of theuser's finger 40, as shown in FIG. 30 . In another suitable arrangement,sensors 52 may be located at different heights along the side portion ofthe user's finger 40. This type of arrangement is illustrated in FIG. 31. As shown in FIG. 31 , sensors 52 may be offset with respect to oneanother (e.g., offset from one another such that one sensor 52 is closerto top housing portion 108 than the other sensor 52). For example,sensor 52 that is closer to the tip of finger 40 may be higher andcloser to top housing portion 108 than the other sensor 52 that iscloser to the back end of the fingertip. This type of arrangement mayhelp ensure that front sensors 52 do not inadvertently strike thesurface that finger 40 is contacting while wearing device 10. Ifdesired, control circuitry 14 may process sensor data to compensate forany decreased sensitivity in sensors 52 that results from being higherup on the side of the finger.

It may be desirable to incorporate biasing structures in device 10 tokeep device 10 appropriately positioned on finger 40. For example, whenside housing portion 106 is closer to the back end of the fingertip, asin the examples of FIGS. 30 and 31 , biasing structure 120 may be usedto bias top housing portion 108 towards finger 40. Biasing structure 120(e.g., a spring) may help minimize rotation of housing 108 away fromfinger 40 about pivot point 118.

FIG. 32 is a side view of device 10 showing how side housing portion 106may have a curved portion such as curved portion 106C. Curved portion106C may be curved away from the middle phalanx to minimize bulging offinger 40 at location 124, which might otherwise cause device 10 tobecome misplaced on finger 40.

FIG. 33 is a cross-sectional side view of device 10 showing how a strapmay be used to help secure device 10 to finger 40. Strap 40 may have afirst end coupled to a first of side portions 106 and a second endcoupled to a second of side portions 106. Strap 40 may be elastic (e.g.,may be formed from an elastomeric polymer), may be formed from fabric,and/or may be formed from other materials. Strap 40 may be permanentlyattached to side housing portions 106 or may be removable (e.g., may becoupled to portions 106 with an attachment structure such as a buckle,snap, tie, magnets, etc.). Strap 40 may extend around a bottom portionof finger 40 closer to the middle phalanx of finger 40 so that thefinger pad of finger 40 can contact external surfaces withoutinterference by strap 40.

As described above, one aspect of the present technology is thegathering and use of information such as sensor information. The presentdisclosure contemplates that in some instances, this gathered data mayinclude personal information data that uniquely identifies or can beused to contact or locate a specific person. Such personal informationdata can include demographic data, location-based data, telephonenumbers, email addresses, twitter ID's, home addresses, data or recordsrelating to a user's health or level of fitness (e.g., vital signsmeasurements, medication information, exercise information), date ofbirth, eyeglasses prescription, username, password, biometricinformation, or any other identifying or personal information.

The present disclosure recognizes that the use of such personalinformation, in the present technology, can be used to the benefit ofusers. For example, the personal information data can be used to delivertargeted content that is of greater interest to the user. Accordingly,use of such personal information data enables users to have control ofthe delivered content. Further, other uses for personal information datathat benefit the user are also contemplated by the present disclosure.For instance, health and fitness data may be used to provide insightsinto a user's general wellness, or may be used as positive feedback toindividuals using technology to pursue wellness goals.

The present disclosure contemplates that the entities responsible forthe collection, analysis, disclosure, transfer, storage, or other use ofsuch personal information data will comply with well-established privacypolicies and/or privacy practices. In particular, such entities shouldimplement and consistently use privacy policies and practices that aregenerally recognized as meeting or exceeding industry or governmentalrequirements for maintaining personal information data private andsecure. Such policies should be easily accessible by users, and shouldbe updated as the collection and/or use of data changes. Personalinformation from users should be collected for legitimate and reasonableuses of the entity and not shared or sold outside of those legitimateuses. Further, such collection/sharing should occur after receiving theinformed consent of the users. Additionally, such entities shouldconsider taking any needed steps for safeguarding and securing access tosuch personal information data and ensuring that others with access tothe personal information data adhere to their privacy policies andprocedures. Further, such entities can subject themselves to evaluationby third parties to certify their adherence to widely accepted privacypolicies and practices. In addition, policies and practices should beadapted for the particular types of personal information data beingcollected and/or accessed and adapted to applicable laws and standards,including jurisdiction-specific considerations. For instance, in theUnited States, collection of or access to certain health data may begoverned by federal and/or state laws, such as the Health InsurancePortability and Accountability Act (HIPAA), whereas health data in othercountries may be subject to other regulations and policies and should behandled accordingly. Hence different privacy practices should bemaintained for different personal data types in each country.

Despite the foregoing, the present disclosure also contemplatesembodiments in which users selectively block the use of, or access to,personal information data. That is, the present disclosure contemplatesthat hardware and/or software elements can be provided to prevent orblock access to such personal information data. For example, the presenttechnology can be configured to allow users to select to “opt in” or“opt out” of participation in the collection of personal informationdata during registration for services or anytime thereafter. In anotherexample, users can select not to provide certain types of user data. Inyet another example, users can select to limit the length of timeuser-specific data is maintained. In addition to providing “opt in” and“opt out” options, the present disclosure contemplates providingnotifications relating to the access or use of personal information. Forinstance, a user may be notified upon downloading an application (“app”)that their personal information data will be accessed and then remindedagain just before personal information data is accessed by the app.

Moreover, it is the intent of the present disclosure that personalinformation data should be managed and handled in a way to minimizerisks of unintentional or unauthorized access or use. Risk can beminimized by limiting the collection of data and deleting data once itis no longer needed. In addition, and when applicable, including incertain health related applications, data de-identification can be usedto protect a user's privacy. De-identification may be facilitated, whenappropriate, by removing specific identifiers (e.g., date of birth,etc.), controlling the amount or specificity of data stored (e.g.,collecting location data at a city level rather than at an addresslevel), controlling how data is stored (e.g., aggregating data acrossusers), and/or other methods.

Therefore, although the present disclosure broadly covers use ofpersonal information data to implement one or more various disclosedembodiments, the present disclosure also contemplates that the variousembodiments can also be implemented without the need for accessing suchpersonal information data. That is, the various embodiments of thepresent technology are not rendered inoperable due to the lack of all ora portion of such personal information data.

The foregoing is merely illustrative and various modifications can bemade to the described embodiments. The foregoing embodiments may beimplemented individually or in any combination.

What is claimed is:
 1. A finger device configured to be worn on a fingerof a user, comprising: a housing configured to be mounted on the finger;a flexible membrane coupled to the housing that rests against a sideportion of the finger and that moves in response to movement of thefinger; and a self-mixing optical sensor that measures changes in adistance between the self-mixing optical sensor and the flexiblemembrane.
 2. The finger device defined in claim 1 wherein theself-mixing optical sensor comprises a laser and an integratedphotodiode.
 3. The finger device defined in claim 2 further comprisingcontrol circuitry that sends control signals to an electronic devicebased on the changes in the distance.
 4. The finger device defined inclaim 3 wherein the control circuitry modulates a drive current appliedto the laser.
 5. The finger device defined in claim 1 wherein theself-mixing optical sensor has submicron resolution.
 6. A finger deviceconfigured to be worn on a finger of a user, comprising: a housingconfigured to be coupled to the finger without covering a lower fingerpad surface of the finger; a flexible membrane configured to restagainst a side of the finger; a proximity sensor coupled to the housingand separated from the flexible membrane by a cavity, wherein theproximity sensor measures changes in a distance separating the proximitysensor from the flexible membrane; and control circuitry configured togather input from the proximity sensor as the finger moves.
 7. Thefinger device defined in claim 6 wherein the proximity sensor comprisesa capacitive proximity sensor.
 8. The finger device defined in claim 6wherein the proximity sensor comprises a self-mixing interferometricoptical proximity sensor.
 9. The finger device defined in claim 8wherein the self-mixing interferometric optical proximity sensorcomprises a vertical cavity surface emitting laser.
 10. The fingerdevice defined in claim 9 wherein the self-mixing interferometricoptical proximity sensor comprises a photodiode and wherein the controlcircuitry includes a drive circuit configured to modulate the verticalcavity surface emitting laser and includes a sense circuit configured touse the photodiode to measure corresponding self-mixing fluctuations inoutput light intensity from the vertical cavity surface emitting laser.11. The finger device defined in claim 10 wherein the vertical cavitysurface emitting laser comprises a laser cavity and wherein thephotodiode is integrated in the laser cavity.
 12. The finger devicedefined in claim 10 wherein the photodiode forms a ring around thevertical cavity surface emitting laser.
 13. The finger device defined inclaim 10 wherein the vertical cavity surface emitting laser is stackedon top of the photodiode.
 14. The finger device defined in claim 6wherein the proximity sensor is one of multiple proximity sensors thatmeasure movement of the finger as the lower finger pad surface is movedby a thumb finger.
 15. The finger device defined in claim 6 wherein theproximity sensor is one of multiple proximity sensors that measuremovement of the finger as the lower finger pad surface is moved by asurface.
 16. A finger device configured to be worn on a finger of auser, comprising: a housing having sidewall portions that extend downfirst and second sides of the finger and that leave the finger padexposed; a flexible membrane that rests against the first side of thefinger and that moves in response to movement of the finger pad; adistance sensor separated from the flexible membrane by a cavity,wherein the distance sensor measures a distance separating the distancesensor from the flexible membrane; and control circuitry that sendscontrol signals to an electronic device based on the distance.
 17. Thefinger device defined in claim 16 wherein the distance sensor comprisesa self-mixing optical distance sensor.
 18. The finger device defined inclaim 17 wherein the self-mixing optical distance sensor comprises avertical cavity surface emitting laser.
 19. The finger device defined inclaim 18 wherein the self-mixing optical distance sensor comprises aresonant cavity photodiode.
 20. The finger device defined in claim 16further comprising: an additional flexible membrane that rests againstthe second side of the finger and that moves in response to movement ofthe finger pad; and an additional distance sensor that measures anadditional distance to the additional flexible membrane, wherein thecontrol circuitry uses the distance and the additional distance todetect front-to-back and side-to-side movements of the finger pad.